Gravity is a fundamental force of nature that attracts two bodies toward each other. Its characteristics and effects can be described from different perspectives:
Classical Physics (Newtonian Gravity)
In the framework of classical physics, gravity is described by Isaac Newton's Law of Universal Gravitation. According to Newton:
Law of Universal Gravitation: Every mass exerts an attractive force on every other mass. This force is proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Modern Physics (General Relativity)
Albert Einstein's theory of General Relativity provides a more comprehensive description of gravity:
General Relativity: Gravity is not seen as a force but as a curvature of spacetime caused by the presence of mass and energy. Massive objects like planets and stars warp the fabric of spacetime around them, and objects move along the curved paths (geodesics) created by this curvature.
Curvature of Spacetime: The more massive an object, the more it warps spacetime around it. This curvature directs the motion of other objects, which we perceive as gravitational attraction.
Einstein's Field Equations: These are a set of ten interrelated differential equations that describe how matter and energy influence spacetime curvature.
Effects of Gravity
On Earth: Gravity gives weight to physical objects and causes objects to fall toward the ground when dropped.
In the Universe: Gravity governs the motion of planets, stars, galaxies, and even light. It is responsible for the formation of celestial bodies, the orbits of planets around stars, and the structure of the universe on large scales.
